Dual image acquisition can be a useful feature in the field of endoscopy. Two video streams of the same scene are captured, but each of the captured image streams has different associated characteristics such as a variation in light spectrum, depth of field, or light intensity. In prior dual image systems, images have generally been collected, split in image space, and then focused onto two independent detectors. Such a configuration allows for more versatility than a single image acquisition system, but is generally more expensive and complex, requiring at least two sensors and associated electronics and mounting assemblies.
Some prior art systems do capture multiple images from a single chip, however they generally contain a beamsplitter in the image space of the camera. Such designs have significant limitations due to lack of flexibility in positioning desired optical elements such as filters, lenses, and other elements in the optical paths after the beam is split. Further, the cost of a dual image system may be higher due to the duplication of certain optical components used in focusing and detecting the image light of the dual channels.
What is needed are devices and methods to enable an endoscopic camera to acquire dual images in a cost effective manner. What is further needed are devices allowing the use of varied existing endoscopes for dual imaging applications, and allowing the detection of the varied characteristics in the dual images.